Fireplaces have been used as a source of heat as early as the primative days, and especially before the advent of heating stoves and later the central heating system. Originally, these fireplaces were open and unprotected and were fire hazards. Later, wire screens were produced to cover the fireplace opening and these afforded some protection against embers escaping from the fireplace. However, open fireplaces and those protected by a wire screen, are extremely inefficient as sources for heating a room, since most of the heat is vented through the chimney.
Thereafter, fireplace enclosures with glass doors or panels were developed to prevent heat from the area to be heated from being vented through the chimney, and the room was heated by radiation from the glass. This also solved the problem of embers escaping from the fireplace, and efficiency was slightly improved.
U.S. Pat. No. 3,870,032, issued Mar. 11, 1975, to Lydie et al., discloses a fireplace enclosure with glass doors and in addition discloses decorative apertured panels at the bottom and top of the enclosure to provide air openings into the fireplace.
With the advent of the energy shortage many attempts were made to increase the efficiency of the fireplace closure by installing heat exchange devices within the fireplace, including means to pick up heat from the fire and expell the heated air to the room.
U.S. Pat. No. 3,955,553, issued May 11, 1976, to Soeffker, discloses a heat exchanger which is placed within an existing fireplace and comprises a manifold exteriorly of the fireplace and connected to a forced air blower. A plurality of upright tubes have their lower ends connected to the manifold and have their intermediate portions disposed below, to the rear of and then extending forwardly of the fireplace grate, the upper ends of the tubes being open so that forced, heated air is returned to the room. This was a good solution to the energy-loss problem and increased efficiency of the fireplace to a marked degree.
However, some problems still existed in the Soeffker patent construction, and others like it, in that the heat exchanger was built into the fireplace and was separate from the fireplace enclosure and this required that the enclosure be tailor-made for the heat exchanger. My invention overcomes this problem by providing a heat exchanger as a unitary part of the fireplace enclosure so that the combination may be disposed to cover the fireplace opening in the simple manner required for enclosures either of the wire screen or glass door type.